Process for the dyeing and printing of



included in the dyebath or printing paste. .adyestuffs containing more than one sulfo group in the United States Patent O "ce 3,072,455 PROCESS FOR THE DYEING AND PRINTING OF CELLULOSE ESTER FIBERS Alexis Wiasmitinow, Basel, Switzerland, assignor to Sandoz Ltd., Basel, Switzerland No Drawing. Filed Mar. 24, 1961, Ser. No. 97,999

Claims priority, application Switzerland Apr. 1, 1960 14 Claims. (Cl. 8-57) It is known that cellulose ester and ether fibers can be dyed or printed with water-soluble dyestuffs containing a sulfo group. The dyestuif is subsequently fixed, e.g. by steaming. In order to facilitate diffusion of the dyestuff into the fiber, a mild swelling agent for the cellulose ester pr ether, e.g. thiodiglycol or glycerine triacetate, is often When acid molecule are used, it is necessary to employ stronger swelling agents, e.g. thiourea, in larger amounts. This often leads to a marked reduction in the tensile strength of the cellulose ester or ether fiber on steam fixation.

In order to overcome this disadvantage water-soluble dyestuffs, e.g. acid dyestuffs with more than one sulfo group in the molecule, have been fixed on cellulose ester and ether fibers by using in the padding liquor or printing paste, besides the aforenamed dyestuffs and the normal diluents and thickening agents, a salt of thiocyanic acid, a swelling agent of the urea type, a violatil e carboxylic acid and an aliphatic hydroxy compound. In this way steaming is avoided, but the process entails very lengthy drying at low temperatures, e.g. 40-50 C., to bring about fixation, because at higher temperatures the fiber is degraded.

It has now been found that cellulose esters in the form of loose fiber, filaments, yarns, woven fabrics or knitted goods etc. can be dyed or printed with remarkably good success when water-soluble dyestuffs are used in presence of urea and the dyed or printed goods are dried and the dyestuff fixed by treatment in dry heat at a temperature at which the urea melts. In this way dyeings and prints of excellent fastness to water and soaping are obtained 1 in a very short time and the cellulose ester fiber is afforded maximum protection.

The dyestuffs suitable for the process are all the watersoluble metal-free or metal-containing dyestuffs which may contain e.g. one or more 'sulfo, sulfonamide or carboxyl groups, e.g. acid, basic, 1:2 metal complex, reactive, leuco sulfuric acid ester, mordant dyestuffs, etc. The swelling agent can be employed in amounts of about 20-50%, calculated on the weight of the padding liquor or printing paste. Especially good results are obtained with about 25-40% or more particularly 30-40%. The fixation temperature is governed by the melting point of the urea. It is generally higher than 130 C., preferably between about 140 and 150 C. As a precaution, temperatures above 160 C. are generally avoided. The time required for fixation depends on the temperature; generally a few minutes, e.g. 2-5 minutes, are sufiicient. All the diluents, thickening agents, e.g. sodium alginate, and other assistants normally used in the dyeing and printing of cellulose ester fibers can be employed. The process is especially suitable for the dyeing and printing of secondary cellulose acetate fibers. On these fibers the dyestuffs show their full, inherent fastness properties when applied by this process.

In the examples the parts are by weight and the temperatures in degrees centigrade. The figures in brackets after the dyestuff names are the relevant page numbers of the Colour Index, volume I (1956).

Example 1 ,1 3,072,455 Patented Jan. 8, 1963 a padding liquor containing 10 parts of Xylene Cyanole FF (1294), 300 parts of urea, 50 parts of thiodiethylene glycol, parts of sodium alignate (3%) and 640 parts of Water. The padded fabric is dried, heat-treated for 5 minutes at 140, rinsed, soaped at 50-60 and finished. The blue dyeing obtained is fast to washing and soaping.

Example 2 A fabric of cellulose triacetate is printed with a paste consisting of 20 parts of Xylene Milling Yellow 3GL (1036), 50 parts of thiodiethylene glycol, 300 parts of urea, 500 parts of sodium alginate (3%) and parts of water. The printed fabric is dried, heat-treated for 3 minutes at 150, rinsed, soaped at 50-60, rinsed again and finally finished in the normal way.

Example 3 A paste of 20 parts of Lanasyn Brown RL (1340), 50 parts of diethylene glycol monobutyl ether, 300 parts of urea, 500 parts of sodium alginate (3%) and 130 parts of water is printed on secondary cellulose acetate fabric. The print is dried, heat-treated for 5 minutes at rinsed in cold Water, soaped at 60 and rinsed again. A brown print fast to washing and soaping is obtained.

Example 4 A fabric of secondary cellulose acetate is printed with a paste of 20 parts of Lanasyn Grey 2BL (1397), 50 parts of thiodiethylene glycol, 350 parts of urea, 230 parts of water and 350 parts of sodium alginate (3%). The print is dried, heat-treated at 130 for 10 minutes, rinsed in cold water, soaped at 50 and rinsed again. A grey print with good fastness properties is obtained. Other dyestuffs such as Lanasyn Yellow 3GL (1048), Lanasyn Yellow 2RL (1086), Lanasyn Dark Violet RL (1221) etc. give fast prints on acetate fabrics when applied by the method of this example.

Example 6 A cellulose acetate fabric is printed with a paste consisting of 20 parts of Brilliant Alizarine Light Violet FFR (1205), 50 parts of Lyogen TG (registered trademark), 300 parts of urea, 230 parts of Water and 400 parts of sodium alginate (3%). The printed fabric is heat-treated for 5 minutes at 130, rinsed in cold water, soaped at 50, rinsed again and finished. Other dyestuffs of this class, for example Brilliant Alizarine Light Red B (1117), 4B (l203), Alizarine Light Green GNS (1318) etc., can be printed by the same method.

Example 7 A paste of 30 parts of Drimarene Red Z-2B (registered trademark), 100 parts of Lyogen TG (registered trademark), 400 parts of urea, 140 parts of water, 300 parts of sodium alginate (3%) and 30 parts of thiourea is printed on an acetate fabric. The print is dried, heattreated for 5 minutes at 140", rinsed in cold and warm water, soaped at the boil, rinsed again and finished.

Almost all the reactive dyestuffs can be printed by the same method, e.g. Drimarene Yellow Z-SGL Drimarene Blue Z-RL 1 etc.

A fabric of secondary cellulose acetate is padded with 1 Registered trademark 3 Example 8 An acetate fabric is printed with a paste of 10 parts of Rhodamine B extra (1636), 50 parts of Lyogen TG (registered trademark), 350 parts of urea, 290 parts of water and 300 parts of sodium alginate (3%). The print is heat-treated at 135 for 5 minutes and rinsed in cold water. A brilliant pink is obtained.

Almost all other basic dyestuffs, e.g. Tannofiavine T (1619), Auramine O (1619), Saba Phosphine 2R, Rhodamine 6GH extra (1629), Safranine B extra, Tannastrol GO (1646), can be printed on cellulose acetate by the same method.

Example 9 A crepe fabric of cellulose acetate is printed with a paste of 15 parts of Citronine O (1053), 50 parts of Lyogen TG (registered trademark), 250 parts of urea, 285 parts of water and 400 parts of sodium alginate (3%). The print is dried, fixed by treatment for 3 minutes at 150 in dry heat, then rinsed in cold water and dried.

Azo Yellow G (1031), Xylene Light Yellow 2GP (1016) etc. can be printed by the same method.

Example 10 A paste of 40 parts of Sandozol Blue 04B (2495), 50 parts of Lyogen TG (registered trademark), 300 parts of urea, 220 parts of water, 300 parts of sodium alginate (3%), 30 parts of sodium chlorate solution 1:3, 40 parts of ammonium rhodanide solution 1:1, 10 parts of ammonia 25% and 10 parts of ammonium vanadate solution 1% is printed on a cellulose acetate fabric. The print is dried and fixed in 10 minutes at 130, then rinsed in cold water, soaped at 80-90, rinsed and dried. Other dyestufis of the type used in this example are the Sandozol dyestuffs predominately of indigoid character.

Example 11 A printing paste of 30 parts of Prune Pur (1501), 30 parts of acetic acid 30%, 30 parts of formic acid 80- 85%, 300 parts of urea, 300 parts of water, 300 parts of gum tragacanth thickening (6%) and 10 parts of hydrosulfite RFN is printed on a cellulose acetate fabric. The print is dried and heat-treated for 5 minutes at 140, then rinsed in cold water, soaped at 50, rinsed cold and dried. A deep navy blue print is obtained.

When the 30 parts of Prune Pur are replaced by an equivalent amount of Coelestine Blue B (1509), Ultra Blue P (1507), Ultra Violet MO (1500) or Ultra Cyanine ENE, prints with the same good fastness properties are obtained.

Having thus disclosed the invention what I claim is:

1. In a process for pad-dyeing cellulose ester fibers in presence of urea and fixing by treatment in dry heat, the improvement wherein the dyeing is effected with an aciddyeing wool dyestufi as coloring agent.

2. A process according to claim 1, wherein the fibers are secondary cellulose acetate fibers.

3. In a process for pad-dyeing cellulose ester fibers in presence of urea and fixing by treatment in dry heat, the improvement wherein the dyeing is effected with a neutraldyeing wool dyestuff as coloring agent.

4. A process according to claim 3, wherein the fibers are secondary cellulose acetate fibers.

5. In a process for printing cellulose ester fibers in presence of urea and fixing by treatment in dry heat, the improvement wherein the printing is effected with an aciddyeing wool dyestuif as coloring agent.

6. A process according to claim 5, wherein the fibers are secondary cellulose acetate fibers.

7. In a process for printing cellulose ester fibers in presence of urea and fixing by treatment in dry heat, the improvement wherein the printing is effected with a neutral-dyeing Wool dyestulf as coloring agent.

8. A process according to claim 7, wherein the fibers are secondary cellulose acetate fibers.

9. In a process for printing cellulose ester fibers in presence of urea and fixing by treatment in dry heat, the improvement wherein the printing is effected with leuco sulfuric acid dyestulf as coloring agent in presence of thiodiethyleneglycol.

10. A process according to claim 9, wherein the fibers are secondary cellulose acetate fibers.

11. Secondary cellulose acetate fibers dyed according to claim 1.

12. Secondary cellulose acetate fibers dyed according to claim 3.

13. Secondary cellulose acetate fibers printed according to claim 5.

14. Secondary cellulose acetate fibers printed according to claim 7.

References Cited in the file of this patent UNITED STATES PATENTS 2,901,312 Audas Aug. 25, 1959 7 2,928,712 Bradshaw Mar. 15, 1960 2,995,413 Klein et a1 Aug. 8, 1961 

1. IN A PROCESS FOR PAD-DYEING CELLULOSE ESTER FIBERS IN PRESENCE OF UREA AND FIXING BY TREATMENT IN DRY HEAT, THE IMPROVEMENT WHEREIN THE DYEING IS EFFECTED WITH AN ACIDDYEING WOOL DYESTUFF AS COLORING AGENT. 